Northern Iberian spined-loach description

The Northern Iberian spined-loach is a small, bottom-dwelling member of the loach family with an elongated, cylindrical body, covered with indistinct round scales and marked with rows of black spots, which are largest towards the underside. The base of the tail is very long and narrow, and the dorsal fin is located towards the rear of the body. The mouth is situated below the head, and is surrounded by three pairs of fleshy barbels, and, as in many loaches, the Northern Iberian spined-loach has a split, erectile spine below the eye, used in defence against predators (2)(3)(4). Male and female Northern Iberian spined-loaches are similar in appearance (2)(3).

Related species

Northern Iberian spined-loach biology

Relatively little is known about the biology of the Northern Iberian spined-loach. A rather short-lived fish (8), it feeds mainly on aquatic invertebrates, including fly larvae and tiny crustaceans, as well as on unicellular algae(9).

Spawning occurs in spring, between March and May (2)(3)(10), the female selecting a gravel bottom with strong currents, and using the tail fin to dig a trench into which around 200 large eggs are deposited (2)(3). The Northern Iberian spined-loach is reported to form distinct pairs during breeding, and to live for up to three years (8).

Species with a similar range

Northern Iberian spined-loach habitat

This loach inhabits the upper and middle reaches of rivers, where dissolved oxygen levels are higher, and prefers to live in clear, shallow water with a gravel or stony bottom (1)(2)(3)(6). Records of the Northern Iberian spined-loach’s occurrence in reservoirs need confirmation (7).

Northern Iberian spined-loach status

Northern Iberian spined-loach threats

The Northern Iberian spined-loach has declined in abundance and range in recent decades, and has now disappeared from parts of the Duero and Ebro rivers, with remaining populations also becoming more fragmented. The main threats to the species include gravel and water extraction, water pollution, dam construction, the destruction of spawning areas, and the introduction of exotic fish such as pike (Esox lucius), which may act as predators, competitors, or vectors of disease (1)(2)(3)(6)(7).

The decline in the Northern Iberian spined-loach population is predicted to continue at the current rate, putting the species at ever-increasing risk of extinction (1).

Northern Iberian spined-loach conservation

The Northern Iberian spined-loach is listed as Vulnerable in the Spanish Red Book (3) and as Endangered in the Portuguese Red Book (7). It is also listed on Annex III of the Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention) (11).

No specific conservation measures are known to be in place for the conservation of the Northern Iberian spined-loach (3), but recommended actions include effectively controlling non-native fish introductions, controlling gravel extraction, protecting the areas of river in which this small loach lives, undertaking further research into its distribution, biology and ecology, and seeking to minimise the impacts of water extraction and pollution on the aquatic ecosystem (2)(3)(7).

Authentication

Glossary

Simple plants that lack roots, stems and leaves but contain the green pigment chlorophyll. Most occur in marine and freshwater habitats.

Barbels

Fleshy projections near the mouth of some aquatic vertebrates.

Crustaceans

Diverse group of arthropods (a phylum of animals with jointed limbs and a hard chitinous exoskeleton) characterised by the possession of two pairs of antennae, one pair of mandibles (parts of the mouthparts used for handling and processing food) and two pairs of maxillae (appendages used in eating, which are located behind the mandibles). Includes crabs, lobsters, shrimps, slaters, woodlice and barnacles.

Dorsal fin

The unpaired fin found on the back of the body of fish, or the raised structure on the back of most cetaceans.

Endemic

A species or taxonomic group that is only found in one particular country or geographic area.

Embed this Arkive thumbnail link ("portlet") by copying and pasting the code below.

Terms of Use - The displayed portlet may be used as a link from your website to Arkive's online content for private, scientific, conservation or educational purposes only. It may NOT be used within Apps.